Regarding the motive, he said here on Thursday, the police were still investigating it.
"It is all still under investigation but we have also secured two rifles," he said.
The two rifles secured are a jungle carbine and a P2 while those arrested were F and H by their initials.
"We have worked very hard and arrested two people who are now under intensive interrogation," he said.
Due to the attack at Bank Central Asia (BCA) on Jalan Emy Saelan at 11.30am local time on Wednesday Second Brigadier Prawira and Second Brigadier Gustiar Yudhistira died on the scene while Second Brigadier Deddy Edwar suffered shot wounds.
The officers were killed while they were on duty to guard the bank.
The attackers used rifles and snatched one of them before leaving on motorbikes, he said.
Pradopo said police were still conducting investigation on the scene.
National Police`s head of public relations division Senior Commissioner Boy Rafli Amar meanwhile said that police anti-terror unit Densus 88 had been involved to chase the other two suspects involved in the incident.
Activities at BCA in Palu, the capital of Central Sulawesi meanwhile have now been normal.
"Employees are working as usual serving customers," the chief of the BCA Palu branch office, Jemmy Gosal said.
Jakarta Metropolitan Police`s head of public relations division Senior Commissioner Baharudin Djafar meanwhile said the Jakara Police would step up security at vital objects, VVIP and public service centers such as banks.
Awaluddin, an eye-witness to the incident in Palu said that it was Second Brigadier Januar Yudhistira that was shot first.
"I was just chatting with the victim in front of the police post where the police was standing when suddenly two persons wearing helmet emerged and shot the victim," he said.
Yudhistira fell and the two opened fire again at Second Brigadier Anri Irbal Prawira who was sitting in the police post.
"I jumped behind the post and ran and hid for some time at Millenium swimming pool area nearby, he said.
Dedy Edwar also jumped like me and hid. Awaluddin is a parking attendant at the area.
He said the attackers immediately fled carrying a rifle belonging to one of the police officers on a motorbike while tow other friends were waiting across the street. He said the incident happened very fast.
(ANTARA)
Editor: Ella Syafputri
Copyright © ANTARA 2011
